1. Field of the Invention
The present invention relates to rectifier circuits and, more particularly, to a synchronous rectifier circuit that is impervious to reverse feed.
2. History of the Related Art
Feeder devices with synchronous rectifiers are known per se, and are in use as electric power supplies. In the same way, such devices are known from publications, for example, from O. Kilgenstein, Schaltnetzteile in der Praxis, Wuerzburg, 1992. Each of the known devices has a range of operation that is limited at the top by the maximum output current at which the output voltage is still regulated to the desired value.
If, either temporarily or for long periods, the current requirement is greater than the capacity of a single device and the selection of a similar device of greater capacity is not indicated for certain reasons, then these devices are connected in parallel.
If in one of the devices that is connected together in parallel in this manner, an operating state arises in which either the output voltage drops or the oscillator no longer triggers or interrupts the primary transformer, then the devices that are connected in parallel with the device under consideration feed power back into the device that is either temporarily or permanently out of service, which as a rule leads to the destruction of the controlled rectifier or to a collapse of the output voltage.
The present invention provides an improvement over the prior art by providing a synchronous rectifier circuit that is impervious to reverse feed, and that is fully capable of operation in all operating states.